Police officers escort a Turkish man identified only as Ziya T., suspected of killing Staten Island mom Sarai Sierra who died from a fatal blow to the head in Istanbul in January, outside a security office today in Istanbul, Turkey.AP

Sarai Sierra (AP)

She fought for her life.

The Staten Island woman who was bashed to death by a Turkish vagrant desperately tried to fend off her assailant for half an hour, her killer said in a startling confession to cops.

Identified only as Ziya T., the killer said he had been boozing and huffing glue when he saw Sarai Sierra, 33, taking pictures near a set of railroad tracks in Istanbul at 2:30 p.m.

The suspect, who is being processed in Istanbul, said he got close to the mother of two boys and abruptly attempted to plant a kiss on her.

But Sierra retaliated by bashing him on the bridge of the nose with her cellphone.

“She resisted and hit me in the middle of my forehead with her cellphone, and my nose began to bleed,” he told cops, according to the Turkish newspaper Hurriyet. “I got angry, and hit her as hard as I could.”

Ziya T. socked Sierra with his fist and sent her tumbling down an embankment where she came to rest next to a tunnel entrance.

The suspect, who was collared on the border of Turkey and Syria on Saturday, followed his stunned victim and again began trying to kiss her.

After a vicious 30-minute tussle. Sierra grabbed a nearby rock and smashed it into her attacker’s face in a move that sealed her fate.

Zia T. said he grabbed a large rock and repeatedly beat Sierra until her protests began to subside.

“She picked up a rock and began to hit me with it,” he said. “Then I really lost it — I also picked up a rock and hit her head with it a few times.

Now nearly dead and audibly “croaking,” the suspect said he left Sierra for dead at the entrance to the tunnel.

HIs face covered in scratches from the confrontation, Ziya T. returned to the scene of the grisly confrontation the next and day saw Sarai’s lifeless corpse. He covered her body with blankets, placed her clothing in a garbage can and tossed her cellphone and computer into the nearby Bosphorus Sea.

Ziya T. remained in Istanbul after the killing until he heard about the slaying while sitting in a cafe. He said he had no idea the woman was American until he saw media reports of the slaying.

Suddenly desperate for an escape, Ziya T. sold off his meager possessions – a bed and a handcart – for 60 Turkish liras to pay for a bus trip to his brother’s home in a remote region near the Syrian border.

Figuring that his best chance to elude capture would be slipping into the chaos of that country’s civil war, Ziya T. said he walked on foot over the border and told fighters on the other side that he had come to aid in their struggle.

Ziya T. was quickly absorbed into their ranks and sustained a leg wound in battle. The wanted vagrant was placed in a Syrian resistance hospital for 10 days. He told cops that he resolved to turn himself in for Sarai’s murder after he recovered.

But Turkish news reports contend that Syrian fighters eventually caught wind of the strange combatant’s wanted status and turned him over to Syrian police who arranged for a transfer to Turkish authorities.

The suspect was arrested on the Syrian Turkish border Saturday and transported to Istanbul where he remains.